Economic Assumptions Used in Measuring Interests that Continue to be Held Related to Securitization Transactions (Detail)	12 Months Ended
Mar. 31, 2010	Mar. 31, 2009
Direct financing leases \| Minimum
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Expected credit loss	1.51%	1.27%
Discount rate	2.33%	1.92%
Annual prepayment rate	6.24%	3.70%
Direct financing leases \| Maximum
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Expected credit loss	1.55%	1.52%
Discount rate	4.28%	11.43%
Annual prepayment rate	6.59%	6.52%
Installment Commercial Mortgage Loans
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Expected credit loss		0.86%
Discount rate		2.60%
Annual prepayment rate		1.15%

The discount rate which is used to value residual cash flows generated by financial assets of the securitization or asset-backed financing arrangement. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4 and FIN46(R)-8
-Paragraph B11
-Subparagraph b(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph h(3)

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- Definition

The rate at which principal will not be repaid on securitized financial assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Estimated speed of prepayments of principal on financial assets. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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